🦕 DinosaursGrade 4Reading: grades 3-4RoundingAdditionSubtractionMultiplicationDivision

Case of the Cretaceous Crook

Someone snatched the famous golden T. rex skull right out of the Thunder Valley Dino Park museum. The night guard saw a shadow dash past the fossil hall and vanish into the fern garden. It is up to you to track down the Cretaceous Crook before the trail goes cold.

Suspects

Possible suspects

Cross off a row as each clue rules it out. On screen, tap a row.

21 of 21 still in play

Name	Dino Type	Special Trick	Footprint	Scale Color	Weak Spot
Spike	Velociraptor	dig a tunnel	big clawed track	striped scales	loud roars
Sandy	Triceratops	stomp a quake	small clawed track	green scales	loud roars
Clawdia	Triceratops	dig a tunnel	big clawed track	striped scales	bright lights
Tilly	Stegosaurus	leap a fence	big clawed track	brown scales	bright lights
Trixie	Stegosaurus	dig a tunnel	big clawed track	striped scales	bright lights
Pebble	Tyrannosaurus	glide on wind	big clawed track	green scales	loud roars
Bronto	Velociraptor	dig a tunnel	big clawed track	green scales	bright lights
Theo	Velociraptor	stomp a quake	small clawed track	striped scales	loud roars
Ziggy	Tyrannosaurus	stomp a quake	small clawed track	green scales	loud roars
Cole	Velociraptor	glide on wind	small clawed track	striped scales	loud roars
Juno	Pterodactyl	whip a tail	small clawed track	green scales	loud roars
Maia	Stegosaurus	whip a tail	small clawed track	striped scales	bright lights
Dot	Tyrannosaurus	stomp a quake	big clawed track	green scales	bright lights
Ferny	Pterodactyl	leap a fence	small clawed track	striped scales	loud roars
Rocky	Velociraptor	leap a fence	small clawed track	brown scales	cold rain
Rexford	Velociraptor	whip a tail	big clawed track	green scales	loud roars
Bram	Stegosaurus	glide on wind	big clawed track	green scales	cold rain
Mossy	Tyrannosaurus	glide on wind	small clawed track	striped scales	loud roars
Vela	Velociraptor	stomp a quake	small clawed track	green scales	cold rain
Dax	Stegosaurus	dig a tunnel	small clawed track	striped scales	loud roars
Comet	Triceratops	whip a tail	big clawed track	striped scales	cold rain

Clue 1

Rounding

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

50000

310

300

470

500000

3100000

1400

470

31000

700

3100000

50000

70000

300

31000

1400000

31000

300

700

470

300

Round 50,425 to the nearest ten thousandT

Round 721 to the nearest hundredN

Round 545,229 to the nearest hundred thousandR

Round 31,155 to the nearest thousandA

Round 289 to the nearest hundredE

Round 3,066,947 to the nearest hundred thousandO

Round 67,365 to the nearest ten thousandL

Round 1,371 to the nearest hundredK

Round 468 to the nearest tenC

Round 72 to the nearest tenF

Round 312 to the nearest tenH

Round 1,367,829 to the nearest hundred thousandP

0/12 letters found

Clue 2

Addition

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

5980

6031

6587

5980

3205

3924

3205

5980

7717

2112

8171

9630

8079

5980

3924

8977

6587

5980

8079

8977

2112

8171

9630

8696

2112

5152

5980

9630

8696

1947 + 4033 =A

916 + 1196 =E

3024 + 5147 =D

3769 + 5861 =T

5440 + 3537 =K

1507 + 1698 =L

3832 + 4864 =H

4196 + 1835 =S

4473 + 3606 =R

2055 + 4532 =M

2165 + 2987 =P

1815 + 2109 =C

3262 + 4455 =W

0/13 letters found

Clue 3

Subtraction

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

6246

4045

6079

6246

3721

3619

2150

3397

6246

3721

6783

3619

8748

7018

8018

5634

7556

8748

7018

2262

6246

5479

8018

6079

3619

3721

8018

6246

3721

10626 - 4380 =A

7238 - 4976 =H

11985 - 4429 =W

6359 - 4209 =S

8337 - 1319 =T

5960 - 2341 =D

7105 - 1626 =L

6795 - 3398 =C

9243 - 3164 =U

10041 - 1293 =I

6213 - 579 =F

6041 - 1996 =G

9599 - 1581 =O

4972 - 1251 =R

7559 - 776 =E

0/15 letters found

Clue 4

Multiplication facts (1–12)

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

120

108

120

100

120

3 × 9 =A

7 × 9 =F

3 × 12 =I

3 × 7 =E

7 × 2 =T

9 × 12 =P

6 × 3 =R

12 × 10 =S

7 × 10 =C

8 × 1 =D

10 × 10 =N

11 × 7 =H

4 × 11 =L

0/13 letters found

Clue 5

Division facts (1–12) — the last clue

First solve each problem. Then find each answer in the list below and cross that sentence out. One sentence will be left — that's exactly what the villain did!

Step 1 — solve these

35 ÷ 7 = ?

36 ÷ 4 = ?

16 ÷ 2 = ?

18 ÷ 9 = ?

144 ÷ 12 = ?

70 ÷ 7 = ?

12 ÷ 2 = ?

63 ÷ 9 = ?

9 ÷ 9 = ?

66 ÷ 6 = ?

6 ÷ 2 = ?

Step 2 — cross out the sentence with each answer

1.The villain swoops from the roof, then leaps a fence.

2.The villain swoops from the roof, then whips a tail.

3.The villain swings a spiked tail, then leaps a fence.

4.The villain sneaks on quick claws, then stomps a quake.

5.The villain bites through the lock, then glides on wind.

6.The villain sneaks on quick claws, then whips a tail.

7.The villain bites through the lock, then leaps a fence.

8.The villain swings a spiked tail, then digs a tunnel.

9.The villain sneaks on quick claws, then glides on wind.

10.The villain swings a spiked tail, then stomps a quake.

11.The villain bites through the lock, then whips a tail.

12.The villain charges with three horns, then stomps a quake.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — Case of the Cretaceous Crook

Culprit: Theo (Velociraptor · stomp a quake · small clawed track · striped scales · loud roars)

Clue 1 (Rounding): "THE CROOK CANNOT LEAP A FENCE"
Round 50,425 to the nearest ten thousand = 50000 (T) · Round 721 to the nearest hundred = 700 (N) · Round 545,229 to the nearest hundred thousand = 500000 (R) · Round 31,155 to the nearest thousand = 31000 (A) · Round 289 to the nearest hundred = 300 (E) · Round 3,066,947 to the nearest hundred thousand = 3100000 (O) · Round 67,365 to the nearest ten thousand = 70000 (L) · Round 1,371 to the nearest hundred = 1400 (K) · Round 468 to the nearest ten = 470 (C) · Round 72 to the nearest ten = 70 (F) · Round 312 to the nearest ten = 310 (H) · Round 1,367,829 to the nearest hundred thousand = 1400000 (P)
Clue 2 (Addition): "A SMALL CLAWED TRACK MARKED THE PATH"
1947 + 4033 = 5980 (A) · 916 + 1196 = 2112 (E) · 3024 + 5147 = 8171 (D) · 3769 + 5861 = 9630 (T) · 5440 + 3537 = 8977 (K) · 1507 + 1698 = 3205 (L) · 3832 + 4864 = 8696 (H) · 4196 + 1835 = 6031 (S) · 4473 + 3606 = 8079 (R) · 2055 + 4532 = 6587 (M) · 2165 + 2987 = 5152 (P) · 1815 + 2109 = 3924 (C) · 3262 + 4455 = 7717 (W)
Clue 3 (Subtraction): "A GUARD SCARED IT OFF WITH A LOUD ROAR"
10626 - 4380 = 6246 (A) · 7238 - 4976 = 2262 (H) · 11985 - 4429 = 7556 (W) · 6359 - 4209 = 2150 (S) · 8337 - 1319 = 7018 (T) · 5960 - 2341 = 3619 (D) · 7105 - 1626 = 5479 (L) · 6795 - 3398 = 3397 (C) · 9243 - 3164 = 6079 (U) · 10041 - 1293 = 8748 (I) · 6213 - 579 = 5634 (F) · 6041 - 1996 = 4045 (G) · 9599 - 1581 = 8018 (O) · 4972 - 1251 = 3721 (R) · 7559 - 776 = 6783 (E)
Clue 4 (Multiplication facts (1–12)): "A STRIPED SCALE FELL IN THE FERNS"
3 × 9 = 27 (A) · 7 × 9 = 63 (F) · 3 × 12 = 36 (I) · 3 × 7 = 21 (E) · 7 × 2 = 14 (T) · 9 × 12 = 108 (P) · 6 × 3 = 18 (R) · 12 × 10 = 120 (S) · 7 × 10 = 70 (C) · 8 × 1 = 8 (D) · 10 × 10 = 100 (N) · 11 × 7 = 77 (H) · 4 × 11 = 44 (L)
Clue 5 (Division facts (1–12)): surviving statement (box 4) → Theo
35 ÷ 7 = 5 · 36 ÷ 4 = 9 · 16 ÷ 2 = 8 · 18 ÷ 9 = 2 · 144 ÷ 12 = 12 · 70 ÷ 7 = 10 · 12 ÷ 2 = 6 · 63 ÷ 9 = 7 · 9 ÷ 9 = 1 · 66 ÷ 6 = 11 · 6 ÷ 2 = 3

About this mystery

Grade level: Grade 4 math
Math topics: Rounding, Addition, Subtraction, Multiplication, Division
Reading level: grades 3-4
Theme: Case of the Cretaceous Crook — set in the Thunder Valley Dino Park
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects